We consider optimal control of fractional in time (subdiffusive, i.e., for \begin{document}$$ 0<\gamma <1 $$\end{document}) semilinear parabolic PDEs associated with various notions of diffusion operators in an unifying fashion. Under general assumptions on the nonlinearity we \begin{document}$$\mathsf{first\;show}$$\end{document} the existence and regularity of solutions to the forward and the associated \begin{document}$$\mathsf{backward\;(adjoint)}$$\end{document} problems. In the second part, we prove existence of optimal \begin{document}$$\mathsf{controls }$$\end{document} and characterize the associated \begin{document}$$\mathsf{first\;order}$$\end{document} optimality conditions. Several examples involving fractional in time (and some fractional in space diffusion) equations are described in detail. The most challenging obstacle we overcome is the failure of the semigroup property for the semilinear problem in any scaling of (frequency-domain) Hilbert spaces.
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Control problems with vanishing Lie Bracket arising from complete odd circulant evolutionary games
We study an optimal control problem arising from a generalization of rock-paper-scissors in which the number of strategies may be selected from any positive odd number greater than 1 and in which the payoff to the winner is controlled by a control variable \begin{document}$$ \gamma $$\end{document}. Using the replicator dynamics as the equations of motion, we show that a quasi-linearization of the problem admits a special optimal control form in which explicit dynamics for the controller can be identified. We show that all optimal controls must satisfy a specific second order differential equation parameterized by the number of strategies in the game. We show that as the number of strategies increases, a limiting case admits a closed form for the open-loop optimal control. In performing our analysis we show necessary conditions on an optimal control problem that allow this analytic approach to function.
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- Award ID(s):
- 1932991
- PAR ID:
- 10317095
- Date Published:
- Journal Name:
- Journal of Dynamics & Games
- Volume:
- 0
- Issue:
- 0
- ISSN:
- 2164-6066
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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